A banana slug can be 6-8 inches and their erect penis can be just as long. Also, their penises emerge from their heads. After sex, banana slugs eat each others penises.
17
Cymothoa exigua is a type of parasite that enters through fish's gills, eats their tongue, and then replaces it.
6
15% of snails survive digestion by birds and are found alive in their droppings, potentially leading to the spread of snail populations.
1
The ancestor of all domestic cats is the African Wild Cat which still exists today.
12
Christmas Island has bridges for crabs to stop them getting run over during the mass migration.
9
The elephant brain weighs about 6,000g.
274